Shobudani Asagi Goma

This is a very very hard stone, the color is Asagi, and
there is a fair amount of non-invasive Goma present, giving it a very subtle
speckled pattern.

This is a very consistent, very hard, uber-fine stone; it
would be very difficult to find a better razor hone. With a full set of Nagura –
you can go from bevel to super final-finish right on this one hone. So far as
edge quality is concerned – this stone is capable of producing the finest,
sharpest and smoothest edges possible.

However, super-hard stones like this require a good amount
of practice and skill-development to get ‘there’.